A good example that a meter reading, or a scope or spectrum analyser trace, is not a measurement but merely raw data. To extract a measurement you need to fully understand your apparatus and eliminate errors both in the raw data and in the subsequent data analysis. People can fail to do this when the raw data appears to show what they were expecting to see.simon7000 said:
The results of the tests were given as 8/13 and 9/13.
Per: ABX Binomial Probability Table
8/13 - 29% probability that the result was due to random guessing
9/13 - 13% probability that the result was due to random guessing
Both appear to be far below that usually required for a positive outcome in a scientific test (5% or 1%).
What Utter Fckng Garbage you post !
You think the rest of the members at this forum are total retards ?
Mr. Curl posted 2 Xerox'd pages of the magazine.
Can I impress you with a picture of the entire magazine ?
Or how about a thousand pictures of a thousand audio mag editions ?
Yes, even I can hear the difference between a garbage carbon resistor and a decent MF at the input of a moving coil pre-pre.
What relevance has that to any talk about insanely priced resistors, dressed ones or bucknaked ?
Absolutely Zero, it's the SOB of GEB !!!
(Please excuse my language. In winter time, you only have to post the word screw, to make me fantasize of the fun it would be to reach for a box of 4'' fiberboard screws and drill a hundred of them in your head)
Jacco relax please... nice that we are 3 at last...thaT all thread restart after I post my impression on the load resistor.... that's all
You posted you suffer from tinnitus.
Option A : You fell from the stairs as me, or got beaten senseless by someone as me.
Option B : You belong to the category for tinnitus, you are not the youngest.
You mentioned having tinnitus, yet did not mention it was the effect of an accident, or physical abuse.
Ergo, chances are high you belong to category B.
You are a TT aficionado :
A : your avatar
B : your talk of turntables and phono gain stages.
Ergo, chances are high you belong to category B.
You suffer from tinnitus, yet claim you can distinguish subtle details/differences between MF resistors of different manufacture.
A : you are talking about physical appearance, or oral flavor
B : you refuse to accept your hearing is not exactly A-no-1
Ergo, chances are high you belong to category B
You seek support by other category B members.
Ergo, chances are high you belong to category B
Category B in general is characterised by a refusal of reality.
- nothing wrong with their hearing
- in great physical shape
- denial of anything that confronts their beliefs
- respectless to anyone who does not acknowledge their 'truth'
At least I'm totally willing to accept and acknowledge I'm an idiot.
Option A : You fell from the stairs as me, or got beaten senseless by someone as me.
Option B : You belong to the category for tinnitus, you are not the youngest.
You mentioned having tinnitus, yet did not mention it was the effect of an accident, or physical abuse.
Ergo, chances are high you belong to category B.
You are a TT aficionado :
A : your avatar
B : your talk of turntables and phono gain stages.
Ergo, chances are high you belong to category B.
You suffer from tinnitus, yet claim you can distinguish subtle details/differences between MF resistors of different manufacture.
A : you are talking about physical appearance, or oral flavor
B : you refuse to accept your hearing is not exactly A-no-1
Ergo, chances are high you belong to category B
You seek support by other category B members.
Ergo, chances are high you belong to category B
Category B in general is characterised by a refusal of reality.
- nothing wrong with their hearing
- in great physical shape
- denial of anything that confronts their beliefs
- respectless to anyone who does not acknowledge their 'truth'
At least I'm totally willing to accept and acknowledge I'm an idiot.
Scott,
Turns out yesterday's tests showed a whole new important issue.
Attached are the runs of the resistor by it self and with it being powered by two different types of batteries. Not showing it zoomed in but I think it is clear there is a difference in the system noise based on battery type.
As I have been stuck in my power supply article on how to show and compare battery performance in actual use this has been a great bit of stupidity.
FYI the 12 volt 7 amp hour gel cell has more system noise that the 13 volt 3 amp hour Fe Li PO cells including the mandatory battery protection circuit!
ES
Turns out yesterday's tests showed a whole new important issue.
Attached are the runs of the resistor by it self and with it being powered by two different types of batteries. Not showing it zoomed in but I think it is clear there is a difference in the system noise based on battery type.
As I have been stuck in my power supply article on how to show and compare battery performance in actual use this has been a great bit of stupidity.
FYI the 12 volt 7 amp hour gel cell has more system noise that the 13 volt 3 amp hour Fe Li PO cells including the mandatory battery protection circuit!
ES
Attachments
Gel cells sound 'wobbly'?
Always good to remind people that batteries are not as quiet as they might think they are!
Always good to remind people that batteries are not as quiet as they might think they are!
The NIST battery study is really nice work and we even paid for it. IIRC the floor was <100pV/rt-Hz. I do like to build on others work.
Van der Zeil and all his Phd. students have studied noise in thin films, etc. for decades I don't see having any reasonable expectation for finding some previously unknown directional effects. I also wish you folks would drop the carbon comp as an example (the 741 of resistors).
EDIT - NiCd AA cells measure .05nV down to 10Hz or so.
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The noise floor of the batteries is not the noise floor of the system. The battery actually lowers the system noise floor. I thought that was what was shown.
Carbon composition resistors are used because they are a good noise source, not because they are typical modern resistors. Much easier to see the bad effects. (Yes I recall your bit as using really bad resistors as a noise source.)
The 741 is still in production as are carbon comps and even 2N404s! But you have to look for a 2N107! (Off Topic, I do need an SSM2108 for a service item. Ordered one from the manufacturer's service dept. where it was listed as in stock. Still listed that way but they are unable to ship. So I ordered from a site that from paypal info is in China. I expect to be listing the result on the "is mine a fake thread.")
Edit to the Edit. Yes cells are really low noise which is why just measuring the cell is very tough. But I think the actual useful data is how the batteries reduce the system noise as it is clear they are not adding to it.
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Rochester lists no SSM2108, I might be able to locate some but they are in CA. Rochester is the only guaranteed no fakes source.
EDIT are you sure you don't mean SSM2018? Rochester does have a good stock @$5-6
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but as long as its the right value what carbon composition R effects could matter in mc loading with mV AC signal, room temp operation?
if you think you need a dialed in value for the cart load then you will have to trim no matter how precise the R - the cart mechanical/damping characteristics aren't precise to start or particularly stable even compared to CC R
if you think you need a dialed in value for the cart load then you will have to trim no matter how precise the R - the cart mechanical/damping characteristics aren't precise to start or particularly stable even compared to CC R
I don' think that there are many currently active controversies over the idea that different batteries make different amounts of noise that have different spectral content.
AFAIK battery noise is also dependent on load current and state of charge, so one might question a single point measurement.
Yes the 2018. Rochester has a $250.00 minimum and you have to buy all the pieces, but I'll ask you to look if I strike out on the OEM and the China source.
Worst case I'll be buy that and a bit from R.
Thanks.
BTY I did try the directivity bit using a bridge of 3 metal film and one CC. Reversing the voltage back and forth between plots showed exactly what would be expected. Random bits of difference.
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Normally for audio use you load a battery to about 5-10% of capacity. Unloaded the noise is not measurable other than by heroic method. Loaded more than 10% you are shortening useful life. So there really is a sweet spot to measure system noise.
No it's $100 now they invite you to buy 16 or whatever to make just the minimum.
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